In a book manufacturing process, a plurality of pages are conventionally imposed on each surface of one print sheet to be printed thereon. The printed sheet is folded by a folding machine to make a section and a plurality of sections are stacked. After that, they are stitched and a trimming process is performed to complete a book product such as a book.
Japanese Patent Application Laid-Open No. 2008-302518 discloses a technique which enables a user to check before execution of printing which part of printing data appears on a front surface of printed matter after execution of paper folding. In the technique, an indication of a paper folding method by the user is acquired, a preview image where a printing data image is synthesized with a template image according to the indication of the paper folding method is generated, and the preview image is displayed.
In printing for a print sheet to be folded into a section, required is imposition information indicating positions of areas on the print sheet corresponding to respective pages of a book product and orientations of the respective pages on the print sheet. The imposition information is generated in accordance with a combination of a page size of the book product, a folding method of the print sheet to make the section, a selection whether bag-like portions in the section are to be located on the top or bottom of the section (i.e., a selection of an orientation of the bag-like portions), a selection which side (left side or right side) of the section is to be stitched and the like. However, it is not easy to generate the imposition information under all the conditions.
It is thought that a plurality of sets of imposition information each corresponding to a combination of a page size of book product, a folding method of print sheet, an orientation of bag-like portions in a section, a side of the section to be stitched and the like, are generated in advance, and in operation, one set of imposition information corresponding to an actual book manufacturing process is selected from these sets of imposition information. However, since the number of these sets is large, generation and management of many sets of imposition information are complicated, and there is a possibility that a wrong selection is made when one set of imposition information corresponding to an actual book manufacturing process is selected from many sets of imposition information. In the case where only a suitable set of imposition information is generated when needed, if a condition such as a side of the section to be stitched is changed after generation of the imposition information, complicated work needs to be done again to generate new imposition information. As above, it is difficult to promptly deal with the change of condition. Thus, a new technique where imposition information can be generated easily is required.